I've been sick for so long, what is wrong with me?

[Mumzy97]

I removed my implant on 31st July after having it for 8 months and started feeling unwell on 24th Aug really bad headache, nausea, diziness and cramps. I had unprotected sex on the 16th Aug and had pink and brown spotting for 2 days (25th and 26th Aug) and on the 28th Aug I got my period. Since then I've had nausea, stomach pains, extremely tired, bloating, lower back pain, excess sweating and hot flashes. I went to the doctor and did both urine and blood tests and it doesn't show anything. I had my period on the 23rd Sept I had no cramps which is very strange and I was feeling better but after my period finished the pains came back and now my boobs grew from 38E to a 38FF and for 2 weeks I've had very bad breast pains, my back hurts a lot both upper and lower back pain it's horrible, I keep getting headaches but only on the right side of my head, I am very slim with a flat belly but my belly now looks huge (bloated) and round and I keep having both stomach pains and lower abdominal cramps but don't feel like period pains. What can it be? The doctor thinks it's an indigestion problem but I don't believe it. Could it be that it's my hormones changing after the implant but it's been 2 months would it not be back to normal now or is there a possibility that I might be pregnant which I doubt as I have done tests and they're all negative. HELP PLEASE. Thanks x